Various forms of cargo carrier devices are known for supporting additional cargo on a vehicle. A common type of carrier is a roof mounted rack which spans above the roof of the vehicle which is particularly suited for supporting longer objects including ladders, boats, or any other desired cargo items to be transported which cannot be easily carried on other parts of the vehicle.
Due to the resultant height of a typical roof rack, various attempts have been made to lower the rack to more easily load cargo items thereon. U.S. Pat. No. 5,609,462 by Reimer discloses one example of a cargo carrier for a vehicle which is limited to use with boats and which does not significantly lower the carrier to allow access to most of the carrier from ground level. US application publication no. 2012/0263561 by Li discloses another example of a roof carrier which can be lowered to a loading position, but the device is limited to use with box trucks having a large roof area to support rollers at the rear of the truck to support the carrier as it is displaced between loading and transport positions.
U.S. Pat. No. 7,992,732 by Demiany discloses another example of a cargo supporting device for a vehicle, but the complex arrangements of parts is primarily directed towards loading a cargo box area of a truck, not providing convenient loading access to a roof rack.